This invention relates to a method and composition for surfacechemical displacing of liquid films from solid surfaces. The term film as used herein means a layer of an organic liquid or water which is physically adsorbed to a solid surface.
Typical procedure employed for removing oily films from solid surfaces of electrical, electronic or mechanical equipment involve spraying the solid surfaces with a solvent for the oily material or with an aqueous emulsion which contains a volatile solvent, a penetrant oil and a surface-active agent and functions through surface-chemical activity to displace the oily film.
The solvent film-removing procedure is simply a solvent-washing of the solid surface and depends essentially on the solubility of the oily material in the solvent.
The aqueous emulsion film-removing procedure requires spraying of the emulsion to the solid surface whereby the emulsion is broken on contact with the surface to release the penetrant oil which, with the assistance of the surface-active agent in the water of the emulsion, causes displacement of the oily films from the solid surface. The displacement of the oily film is followed by washing of the solid surface with water to remove residues of the oily film and of the applied emulsion. Optionally, the water-washing step is followed by spraying of a water-displacing composition to remove water from the washed surface.
The above prior art procedures require repeated spraying and, resultingly, the use of large amounts of the solvent or of the aqueous emulsion, as the case may be, to achieve a practical degree of displacement of the oily film from the solid surface. The aqueous emulsion procedure, additionally, has the disadvantages of introducing water which would prove detrimental or injurious in the cleaning of watches, meters and other fine mechanisms, optical equipment with sodium chloride windows, and electrical and electronic equipment containing parts which are damaged by water.